In general, a two-compartment container which serves to accommodate an additive in a container cap and then allow the additive to introduce into the contents within the container upon opening of the container, cap has been known, for example, in U.S. Pat. No. 3,924,741 This container includes a stopper 2 having a skirt 6 screwed onto the outside screw part of the mouth 3 of the bottle 1, and a closure cap 21 for accommodating and discharging an additive 28 while moving up and down coaxially to a cylindrical sleeve 7 within a stopper 2.
The stopper 2 includes a transverse wall 8 in which the lower end of a cylindrical sleeve 7 extending downwardly from the top of ae skirt 6 to the inside of the mouth of a bottle is closed, and a plurality of side apertures 9 that pass through a portion around the side of a transverse wall 8. Shoulders 14, 16 for limiting the movement of the capsule to its upper terminal position are, respectively, formed in the inside of a protrusion part 19 protruded over a horizontal surface so that it forms the upper end of the skirt 6 at the upper end of the cylindrical sleeve 7, and in the outside of an enlarged portion 15 of a cylindrical wall 11 of a corresponding closure cap 21. The top surface of a protrusion part 19 protruded over the horizontal surface so that it forms the upper end of the skirt 6 at the upper end of the cylindrical sleeve 7 is coupled with a surface that supports the disk portion 22 of the closure cap 21, thereby serving to guide a movement of the closure cap 21 upon opening of the side apertures 9 due to the upward movement of the closure cap 21. 27 represents a beverage accommodated in the container 1.
The closure cap 21 includes a cylindrical wall 11 having the circumference of the lower end thereof coupled with the transverse wall 8 so that the closure cap 21 is sealed when the cylindrical wall 11 is initially coupled with the transverse wall 8; a disk portion 22 that performs a stopper function at the upper end of the cylindrical wall 11 when the closure cap 21 falls down; and a dome 25 protruded and connected to a separation groove 26 at the center of the upper end of the disk portion 22 when the dome 25 is separated from the cylindrical wall 11 for communication. 12 represents a lower end having a smaller inside diameter than the cylindrical wall 11 so that it is sealed with the transverse wall 8 and opens the holes 9 when the closure cap 21 rises. 17 represents a flange supporting the disk portion 22. 23, 24 are the disk sides of the disk portion 22.
However, such a structure has been designed so that, when the closure cap 21 rises, a plurality of side apertures 9 on the outside of the lower end of the cylindrical sleeve 7 that forms the stopper 2 are open and the additive 28 is discharged into the container, and at normal times, the additive 28 maintains a sealing state by the transverse wall 8 and a rim 13 which is the end of the lower end 12 having a smaller diameter than the lower part of the cylindrical wall 11. However, if a product is completed, a molding error occurs due to injection molding, penetration of moisture is made due to the nature of synthetic resin materials, a problem arises from the penetration of moisture because the separation groove 26 of the dome 25 is thin. Consequently, an additive powder becomes hard or deformed.
As another technical approach, the cap for storage chamber wherein a protrusion screw portion is placed outside the protrusion part of a stopper, the disk portion of a closure cap is screwed onto the protrusion screw portion, a window for discharging an additive and a horizontal wall are placed in the cylindrical sleeve of the stopper, a whirling pin for whirling an additive is formed in the horizontal wall, and the function of up and down moving means for opening a hole for discharging an additive has been completed by rising the closure cap and mixing an additive with the whirling pin when a screw is unscrewed, has been developed, for example, in U.S. Pat. No. 7,546,919 (inventor: Lee, Jungmin). However, such cap has disadvantages: a shape is deformed due to a lapse of time and a change of temperature, there is a problem in the sealing property because sealing is performed only on one side, and it is likely to make a penetration of moisture.
As another method for solving the problems associated with the sealing property, a new technology in which an elastic attachment/detachment valve is formed only at a portion that greatly requires sealing, the assembling property is improved by temporarily closing an additive upon coupling, and an additive remains in a fixed lower cap upon use after assembling, thereby separating a moving member that is an upper cap and so adding and using the additive, has been developed in WO2005/051775 (inventor: CHO, Youngkook). However, because the attachment/detachment valve must be separately provided in addition to the upper and lower caps, there exists a problem in that the production cost may be increased.
In order to solve the problems, a container stopper designed to deform a shape of the attachment/detachment valve and add a bridge to the lower end of the slider of the lower cap, thereby preventing from separation of the attachment/detachment valve, and also to maintain a binding force and maximize the sealing property upon coupling of the attachment/detachment valve, has been developed in Korean Laid-open Patent Publication No. 10-2011-0086488 (inventor; CHO, Youngkook). However, there remains a problem in the sealing property due to the deformation of the shapes of the attachment/detachment valve and the slider. Further, because an elastic force is reduced if the attachment/detachment valve and the slider are deformed for a long time, it is difficult to maintain an initial sealing property.